Cardiac implant migration inhibiting systems

Abstract

Medical devices, systems, and methods reduce the distance between two locations in tissue, often for treatment of congestive heart failure. In one embodiment an anchor of an implant system may reside within the right ventricle in engagement with the ventricular septum. A tension member may extend from that anchor through the septum and an exterior wall of the left ventricle to a second anchor disposed along an epicardial surface. Deployment of the anchor within the right ventricle may be performed by inserting a guidewire through the septal wall into the right ventricle. The anchor may be inserted into the right ventricle over the guidewire and through a lumen of a catheter. An anchor force may be applied within a desired range to secure the anchors about the septum and epicardial surface. The anchor force may inhibit migration of the anchors relative to the septum and epicardial surface.

What is claimed is: 
     
       1. A system for inhibiting migration of anchors of a heart implant device comprising:
 a tension member having a first end and a second end; 
 a first anchor coupled with the tension member at the first end, the first anchor being configured for anchoring engagement with a first wall of a heart; 
 a second anchor slidably couplable with the tension member, the second anchor having a variable force mode that allows the second anchor to axially slide proximally and distally along the tension member and also having a set force mode that inhibits proximal movement of the second anchor along the tension member, the second anchor being configured for anchoring engagement with a second wall of the heart; and 
 a tension device configured to engage the second anchor so as to apply an anchor force between the tension member and the second anchor; 
 wherein the tension device comprises a shaft comprising a proximal end, a distal end, and a lumen through which the tension member is insertable, and wherein the anchor force is applied by tensioning a portion of the tension member extending proximally of the tension device; 
 wherein the tension device further comprises a tube slidably disposed over the shaft, a compression spring that is operably coupled with the shaft and the tube, and indicia that provides an indication of the anchor force applied between the tension member and the second anchor as the shaft is advanced distally through the tube. 
 
     
     
       2. The system of  claim 1 , wherein the tension device is configured to be disposed outside the heart while applying the anchor force. 
     
     
       3. The system of  claim 1 , wherein the tension device is configured to be disposed outside the heart while applying the anchor force, and wherein the anchor force is within a predetermined range. 
     
     
       4. The system of  claim 1 , wherein the first anchor comprises a proximal end, a distal end, and a lumen extending from the proximal end to the distal end through which a guidewire is insertable so that the first anchor is insertable distally of the first wall over the guidewire. 
     
     
       5. The system of  claim 4 , wherein the first anchor is pivotally coupled with the tension member such that the first anchor comprises a fixed configuration when the guidewire is inserted through the lumen that inhibits rotation of the first anchor relative to the tension member and the first anchor comprises a deployed configuration when the guidewire is removed from the lumen, the deployed configuration allowing rotation of the first anchor relative to the tension member. 
     
     
       6. The system of  claim 1 , wherein the second anchor comprises a lumen through which the tension member is insertable and a lock configured to change the second anchor from the variable force mode to the set force mode, or vice versa. 
     
     
       7. The system of  claim 6 , wherein the lock comprises a spring configured to urge a cam against the tension member disposed within the lumen or wherein the lock comprises a spring configured to urge a lock plate against the tension member disposed within the lumen. 
     
     
       8. The system of  claim 1 , wherein the second anchor is reconfigurable between the variable force mode and the set force mode from outside the patient body from along or within the shaft. 
     
     
       9. The system of  claim 1 , wherein the first anchor and second anchor have substantially the same cross sectional area. 
     
     
       10. The system of  claim 1 , further comprising an elongate flexible body of ingrowth material, the body having an aperture slidably receiving the tension member therethrough so that the body extends laterally from the tension member, the aperture rotationally coupling the elongate body to the tension member so as to facilitate orienting the elongate body by rotation of the tension member, the elongate body positionable between the first wall and the second wall by advancement of the body over the tension member so that the material promotes tissue growth between the first and second wall after the first and second wall are brought into engagement. 
     
     
       11. The system of  claim 1 , wherein the anchor force comprises a force of between about 2 N and about 6 N, which is indicated via the indicia. 
     
     
       12. The system of  claim 11 , wherein the anchor force comprises a force of between about 3 N and about 4 N, which is indicated via the indicia. 
     
     
       13. The system of  claim 1 , wherein the tension device is configured so that the anchor force cannot exceed a force of  4 N. 
     
     
       14. The system of  claim 1 , wherein the tension device is adjustable from a locked configuration to an unlocked configuration and vice versa, wherein:
 in the locked configuration, the shaft is locked in position relative to the tube; and 
 in the unlocked configuration, the shaft is slidable relative to the tube. 
 
     
     
       15. The system of  claim 14 , wherein the tension device is configured so that a force indicator that indicates the anchor force is capable of being zeroed when the tension device is adjusted from the locked configuration to the unlocked configuration. 
     
     
       16. A tension device for engaging a heart anchor system that is engaged with walls of a heart and for applying a force to the heart anchor system, the tension device comprising:
 a shaft having a proximal end, a distal end, and a lumen through which a tension member is insertable; 
 a tube slidably disposed over the shaft; and 
 a compression spring that is operably coupled with the shaft and the tube, wherein:
 the force is applied to the heart anchor system by tensioning a portion of the tension member that extends proximally of the tension device; and 
 the tube comprises indicia that provides an indication of the force applied to the heart anchor system based on the shaft sliding relative to the tube; 
 
 wherein:
 the heart anchor system includes a first anchor that is coupled with a first end of the tension member, the first anchor being configured for anchoring engagement with a first heart wall; 
 the heart anchor system also includes a second anchor that is slidably coupled with the tension member, the second anchor having a variable mode that allows the second anchor to axially slide proximally and distally along the tension member and also having a set force mode that inhibits proximal movement of the second anchor along the tension member, the second anchor being configured for anchoring engagement with a second heart wall; and 
 the force applied to the heart anchor system causes the first heart wall to move toward the second heart wall. 
 
 
     
     
       17. The tension device of  claim 16 , wherein the tension device is configured to be disposed outside the heart while applying the force to the heart anchor system. 
     
     
       18. The tension device of  claim 16 , wherein the force applied to the heart anchor system comprises a force of between about 2 N and about 6 N, which is indicated via the indicia. 
     
     
       19. The tension device of  claim 18 , wherein the force applied to the heart anchor system comprises a force of between about 3 N and about 4 N, which is indicated via the indicia. 
     
     
       20. The tension device of  claim 16 , wherein the tension device is configured so that the force applied to the heart anchor system cannot exceed a force of 4 N. 
     
     
       21. The tension device of  claim 16 , wherein the tension device is adjustable from a locked configuration to an unlocked configuration and vice versa, wherein:
 in the locked configuration, the shaft is locked in position relative to the tube; and 
 in the unlocked configuration, the shaft is slidable relative to the tube. 
 
     
     
       22. The tension device of  claim 21 , wherein the tension device is configured so that a force indicator that indicates the force applied to the heart anchor system is capable of being zeroed when the tension device is adjusted from the locked configuration to the unlocked configuration.